Field of the Invention
The present invention relates to an integrated side member having an impact absorbing structure, and more particularly to an integrated side member having an impact absorbing structure that can secure a space for mounting a battery of an electric vehicle mounted with a high capacity battery and at the same time prevent impact energy from invading into a passenger cabin of the vehicle.
Description of Related Art
Generally, front side members disposed longitudinally at both front lateral sides of a vehicle body are required to have a certain configuration for protecting passengers from impact energy when the vehicle collides with an object.
FIG. 1A shows a vehicle body of a common vehicle, to which a bumper beam 1, crash boxes 3, side members 4 and aprons 2 are combined. As shown in FIG. 1, the vehicle body is required to have a configuration for protecting passengers from impact energy when the vehicle collides with an object. At this time, the front side members 4 play an important role as a shock absorbing device. The front side members 4 are the most important skeletal parts constituting front parts of the vehicle and correspond to rigid members on which an engine and other important parts are mounted.
Such front side members 4 are coupled respectively to the crash boxes 3 which are coupled to opposite sides of the rear end portion of the front bumper beam 1. Each of the front side members includes an impact absorbing portion for relieving the impact from impact energy and an invasion preventing portion for preventing the impact from invading into a passenger compartment.
On the other hand, fuel economy regulations that become more stringent as years go by have facilitated development of electric vehicles by automakers. Environmental friendly vehicles become increasingly wide spread according to support policies on environmental friendly vehicles in worldwide countries in addition to such regulations. Also, competition for increasing traveling distance of environmental friendly vehicles becomes intensified among the automakers. Accordingly, to enhance the traveling distance of an electric vehicle which is a typical environmental friendly vehicle, size of a battery mounted on the vehicle is increasingly enlarged, with the result that weight of the vehicle is inevitably increased.
Such increase in the weight of the vehicle definitely causes increase of impact energy in the event of vehicle impact and hence may seriously affect safety of passengers. Also, in the case of electric vehicles, there are additional regulations related to battery fire, etc. that have to be considered when evaluating impact. Therefore, it is necessary to improve the impact performance.
In other words, in vehicles mounted with the side member according to the related art, since a space for absorbing the impact energy is reduced when a large capacity battery is mounted at a position of a rear lower member 7, as shown in FIG. 1B, there are problems in that electric vehicles cannot utilize the existing vehicle body structure and that it is difficult for the existing structure to meet the regulations related to impact and merchantability because of the increase in the weight of the vehicle.
Furthermore, in the vehicles mounted with the side member according to the related art, structure thereof becomes very complicated and fastening performance deteriorates because of lack of gaps between peripheral parts including a sub-frame and side external parts.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and may not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.